Transgenic technology is widely used in biotechnology. Systems exist for transforming plant cells and regenerating complete plants from the transformed cells; structural gene and gene regulatory regions continue to be identified.
In general, the strength of a given promoter driving a transgene is a function of its inherent properties and the site of integration. Variation in transgene expression due to the site of integration is often referred to as “position effect”. It would be useful to have the ability to alter the strength of a particular promoter in a predictable manner.
It is known that eukaryotic genomes have organizational properties that rely on the ability of the chromosome to establish functional elements that are not adversely affected by elements in close proximity. Polynucleotides that decrease the effects of neighboring sequences or genes are called genetic insulator elements.